Is the U.S. suffering an epidemic of rolling blackouts?

Statistics show squirrels cause about as many blackouts as planned outages.

On March 10, 2012, Rick Santorum published an op-ed on his website that took a series of shots at President Barack Obama’s energy policies.

"This president’s agenda doesn’t just stop with oil and gas," Santorum wrote. "President Obama has also discouraged new electricity generation -- forcing many parts of the country to experience rolling blackouts. That means that millions of Americans will live with a power grid that is second-rate, like a Third World country."

We hadn't noticed the lights cycling off, so we wondered: Are many parts of the country really experiencing "rolling blackouts"?

A "rolling blackout" occurs when a utility intentionally "shuts off the power to an area, turns it back on, and then shuts the power off in a different area," with outages in any given area typically lasting 60 to 90 minutes, according to the California Energy Commission. A utility would do this as a last resort, in order to avoid an even worse situation -- a total power blackout.

This makes it distinct from an uncontrolled outage that occurs when power is disrupted without warning, often by weather or accidents.

So how often do rolling blackouts occur today? We found data from Eaton Corp., a private power management company. They found that weather is the principal cause of power outages in the U.S., according Eaton. In 2011, "planned" outages accounted for just 5 percent of power outages for which a cause could be determined.

For comparison, that’s about as many power outages as were caused by squirrels in 2011.

Because neither Santorum nor experts offered us any evidence that widespread rolling blackouts have occured, we rated the claim Pants On Fire.